Eugen



UNITED STATES PATENT @EErcE;

EUGEN LANGEN, OF COLOGNE, GERMANY.

PROCESS OF REFlNlNG SUGAR.

SPECIFICATION .forming part of Letters Patent No. 495,614, dated April18, 1893.

Application filed February 10, 1892. Serial No. 421,038. (No specimens.)Patented in England January 9,1892, N0. 420; in France January 9,1892.110. 218,563,- in Belgium January 9,1892, No. 97,861; in GermanyJune 23, 1892, Ila-68,189, and in Austria-Hungary August 25, 1892,1l0.3.088 and No. 15,975.

To ttZZ whom it may concern:

Be it known that l, EUGEN LANGEN, a citizen of Prussia, residing atCologne, in the Empire of Germany, have invented new and usefulImprovements in Refining Sugar, (for which 1 have obtained LettersPatent in Great Britain, dated J auuary 9, 1892, No. 420; in France,dated January 9, 1892, No. 218,563; in Belginm,dated January 9, 1892,No. 97,861; in Austria-Hungary, dated August 25, 1892, No. 3,088 and No.15,975, and in Germany, dated June 23, 1892, No. 68,189,) of which thefollowing is a specification.

Thisinvention relates to an improved method of refining sugar wherebyall the sugar obtainable by recrystallization from the afterproducts ofthe refining is led back into the circuit of the refining process in theform of an almost chemically pure sugar solution, so that the refiningis carried out without afterproducts, such as result from the presentmode of refining. For this purpose, the dissolved raw sugar, afterfiltration, is boiled down to a granular filling mass, in the usualmanner and thus the No. 1 product of the refining process is obtained.

The essential feature of the invention consists in the now followingtreatment of the after products resulting from this first treatment. Thefirst sirup, the so called green sirup, is thickened by evaporation inthe usual way in a vacuum pan to a stringy or granular consistency, andthis thickened mass or magma is then subjected while in a hot conditionto the known process of renewed crystallization under motion (such asthe I Wulff or Bock process) consistingin i11- troducing it into vesselsin which the magma is kept continuously in motion by means of suitablestirrers or agitators, while a regulated lowering of the temperature iseffected by suitable known means, such as by the introduction of hot orcold water into the jacket of the vessel, in accordance with therequired separation of sugar from the mass. At the same time extraneoussugar crystals are introduced into the mass which have the effect ofinducing or accelerating the formation of fresh crystals therein. Thecrystalline magma thus produced is then subject to the known process offractional washing Steffans process for the removal of the motherliquor, and which consists in treating the crystalline magma first witha saccharine liquor which approximates in quality to the mother liquoraround the crystals. Such liquor is introduced at the top of the washingvessel and as it penetrates downward, displacing the mother liquor(which is drawn off at the bottom of the vessel) a somewhat betterquality of liquor is introduced at top which in its turn displaces theliquor first introduced, and so on, using a gradually purer liquor untilthe last washing of the crystals is completed by means of perfectly puresaturated sirup. The various washing liquors thus employed are drawn offconsecutively and separately from the washing vessel and are collectedin separate vessels to be used over again with the exception of thefirst, poorest liquor drawn oil, while for the final washing a freshquantity of pure sirup is always employed.

By the above described means the mass is divided into a whitishcrystalline magma, constituting Product No.2, and alow grade sirup,being the mother liquor separated as above. 7 When the last washingliquor passing away from the mass has been pumped off as much aspossible, water is led in thin streams distributed as uniformly aspossible over the surface of the mass. The water becomes saturated withsugar and this solution penetrates through the mass, washes it again andfinally effects the solution of the entire contents of the washingvessel. If this sugar solution on issuing from the bottom of the washingvessel is at first somewhat colored, it is used as boiling liquor forthe No. 1 product while the solution afterward pumped out until thefinal solution of the entire contents of the washing vessel, is employedfor the preparation of the clear liquor.

The low grade sirup first pumped off from the No. 2 product as abovedescribed, is again thickened by evaporation, and is also made tocrystallizeoutaccordin g to the method of crystallization under motionabove described. The mass thus produced is then subjected to centrifugalaction and the resulting sharp grained yellowish granular sugar (No. 3product) is employed for inducin g or accelerating as above described,the formation of crystals in the mass of the No. 2 product. I

As a rule the sirup thrown off from No. 3 product will be of so low aquality with regard to sugar contained in it,that it may be consideredas molasses and led off from the refinery. If this is not the case thesirup is again subjected to the process of crystallization under motion,and the sugar obtained as No. 4 productis introduced either into thesugar obtainable by crystallization from the after products of therefining process, is led back into the circuit of the refining process,

in the form of an almost chemically pure sugar solution, such methodconsisting in first thickening the low grade sirups separated from thecrystals (No. 2 product) obtained from the green sirup, then causingsuch low grade sirup to crystallize by the process of crystallizationunder motion, then returning the granular sugar thus obtained (No. 3product) into the masse cuite of the preceding product (No. 2) in orderto induce or accelerate the formation of crystals therein, and lastlysubmitting the combination of crystals of Nos. 2 and 3 products thusobtained to fractional washing whereby the pure sugar solution firstabove mentioned is obtained.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing Witnesses, this 21st day of January, A. D.1892.

EUGEN LANGEN.

)Vitnesses:

R0131. M. HOOPER, GOTTLIEB LANGEN.

